Code Manual for CONTAIN 2.0 - Federation of American Scientists

where
Table 4-6
Conservation of Energy Equation for the Coolant Pool in Cell i (Concluded)
%c,boil = energy transfer from pool boiling calculated in the lower cell,
see Ww,kil in Table 4-3;
qp,gr,e. = energy dissipation rate in the pool from work done by gravity for explicit
processes
= g{ ‘es,o.t ( ‘es,o.t - Hp,i) + [ W~,~~P+ max( Wp,Co.~,O ) 1 ( Hi - Hp,i) +
WdropQLrop,out- Hp,i) + w~,o.~ ( Hh,oUt- Hp,i) + ws~v,o.t ( Hs~v - Hpj ) }
AQ, =UPj -mP,iu~T,,i,Pi)
Hes,out = mean elevation of origin of engineered systems effluent;
Hdrop,out = mean elevation of origin of dropout liquid directed to the pool;
H hs,out = mean elevation of origin of coolant film runoff from heat
transfer structures;
HSRV = SRV or sparger elevation;
q~k = rate of work done by the atmosphere on the pool
=
dV
-P->
dt
where V~is the gas volume.
and A~ is the flow timestep, ~ is the coolant vapor specific enthalpy, ht is the liquid coolant specific
enthalpy, T,j is the pool saturation temperature, Pi is the cell gas pressure, ~j is the pool mass after
flow step, but before gas equilibration, UPj is the pool internal energy after the interpool flow step,
but before gas equilibration, and U!is the liquid coolant specific energy.
4.4.7 Gas-Pool Equilibration
This section discusses the modeling of gas-pool equilibration that occurs with respect to gas flow,
when the flow is injected into a cell from a flow path that is submerged below the collapsed pool
level in that cell. Gas flowing into a pool from a submerged gas flow path or the dedicated
suppression vent in forward flow is in general equilibrated as discussed below. However, note that
gas equilibration is ignored for the suppression vent in reverse flow, for reasons related to model
Rev. O 4-36 6/30/97